Method and mechanism for centrifugally separating substances



CENTRIFUGALLY SEPARATING SUBSTANCES. LICATION FILED SEPT-4, 1920.

L. D. JONES.

k \L a L. n, JONES; METHOD AND MECHANISM FOR CENTRIFUGALLY SEPARATINGSUBSTANCES.-

APPLICATION FILED SEPT- 4, 1920- 7 1,373,743. Patented Apr. 5, 1921.

3 SHEETSSHEET 2.

IIIII 3 SHEETSSHEET 3- ING SUBSTANCES- Patented Apr. 5, 1921. 32

0D. Toilets;

v (Zorneyfi D. JONES.

, APPLICATION FILED SEPT. 4, I920- METHOD AND MECHANISM FORCENTBIFUGALLY SEPARAT unrrso STATES e rsn'r OFFICE.

LEO D. JONES, 0F PHILADELPHIA. PENNSYLVANIA. ASSIGNOR TO THE SHARPLESSPECIALTY COMPANY, OF WEST CHESTER, PENNSYLVANIA, A CORPORATION OFDELAWARE.

Specification of Letters Patent.

Patented Apr. 5, 1921.

Application filed September 4, 1920. Serial No. 408,336.

for effecting separations where three constituents are. involved, with aview to 1ninimizing the objectionable effects on the separation of thetwo lighter constituents due to changes in the density of the heaviestconstituents and nice adjustments of the dams therefor. as. morespecifically in the treatment of dilute cylinder stock or petroleiunoils containing wax. by subjecting the same together with a heaviercarrier liquid. such as brine. to centrifugal force in a, bowl having aplurality of outlets through which the separated substances aredischarged respectively. It will be understood. however. that while theimproven'ients have a highly important use in the separation of waxfromoil. the principles involved are not to be considered as limited tothis use but are of more general appliaition as, for instance. to theseparation of oil from soap water in which the soap has beenprecipitated by salt.

Specific advantageous functions of the invention are. found in itscapacity for segregating more than two substances by a ma chine havingtwo or more discharge passages and improved means for controlling thedischarge of the separated substances with avoidance of the necessityfor the refinement in construction and adjustment and the elimination of'the sensitiveness of operation involved in the separation of more thantwo constituents by known centrifugal means and methods. and also in thecomparative independence of the sepa 'ation of the two lighterconstituents upon the adjustment of the dams and the specific gravity ofthe heaviest constituent, and vice versn. and the comparativeindependence of the. separation of the two heavier constituents upon theadjustment of the dams and the specific gravity of the lightestconstituent.

As an example of the sensitiveness of the customary practice. considerthe operation of a centrifugal machine designed to effect the dischargeof wax with the carrier liquid through one passage and oil throughanother. Here an increase of inch in the axialdistance of the weir overwhich the wax and carrier liquid flows over that required for normaloperationhas effected a.

change of relations which cause the discharge of oil with the wax, and adecrease of mch from that required for normal operation has been foundto cause the discharge of wax with the oil, whereas in the presentmethod a variation of 5% inch in either di rection in the position ofthe weir for the carrier liquid has been found to have no effect uponthe efliciency of the separation of the wax from the oil.

Variations in the density of the carrier liquid may likewise take )lacewithout substantially effecting the efficiency of the separation of theoil and wax by the. present improvements. whereas a slight variation inthe density of the carrier liquid has heretofore interfered with andprevented the desired separations.

In separating a mixture of three substances each substance may bedischarged separately but it frequently happens that it is desirable ormore convenient to discharge one separately on the one hand, anddischarge a mixture of the other two constituents (usually the heaviertwo) on the other. This is most efiiciently accomplished by stratifyingthe three constituents and controlling the separation according tomyinvention, followed by reuniting the two to be discharged togetherwhile still under the influence of centrifugal force and discharging thetwo products through separate discharge passages. I

The invention is practised by means of the structures set out in thefollowing description and the accompanying drawings in illustrationthereof.

In the drawings, Figure 1 is a broken vertical sectional view of the topof a centrifugal separator bowl constructed in accordance with theinvention; Fig. 2 is a sectional view taken on the line 2-2* of Fig. 1:Fi

3 is a sectional view taken on the line 3*-3" of Fig. 1; Fig. 4 is asectional view taken on the line 4*4* of Fig. 1; Fig. 5 1s a brokenvertical sectional view of the top of a centrifugal bowl of modifiedconstructiontaken on the line *5 of Fig. 6, by which three substancesare separated in the ,bowl under control of respective dams thereforfollowed by discharging two of them together; Fig. 5 6 is a sectionalview taken on the line (i -6 of Fig. 5; and Figs. '2, 8, 9, 9*, and 10are vertical sectional views of vessels designed to illustratediagrammatically conditions involved in the separation of threesubstances, 10 as in the case of petroleum oil containing wax with theuse of brine as a carrier liquid.

The construction illustrated in Figs. 1 to 4 inclusive comprises a bowl1 having a neck 2 connected by a coupling 3 with a spindle 4, bywhich'the bowl is suspended and revolved.

The bowl 1 is, provided at its top with three passages or sets ofpassages 5, 6-6 and 7 for discharging substances'of difi'erentdensities, as oil, waxand brine, which have been Stratified in the bowlby its revolution.

The discharge passages 5 communicate at their inlets with the bowl bodythrough the concentric cylindrical chamber 8, into which the oil, orotherwise the lightest of the separated substances, flows over the ring9, and through passages 5, the passages discharging into the channel 10concentric with 0 the axis of rotation and having the concen-. tricannular dam or ring 11 over which the liquid flows. The ring or dam 11is made exchangeable for dams or rings of different sizes andcharacteristics, for accommodation to different conditions, by means ofthe collar 12 detachably connected with-the neck 2 for engaging suchdams thereto.

The discharge passages 6 and 6 are connected through the cylindricalchamber 13,

which is disposed concentrically with. the

bowl in the neck thereof and has near its top the concentric ring orannular dam 14, the chambers 8 and 13 being separated by the diaphragm15.

The discharge passages 7 lead from the interior of the bowl body 1, frominlets exterior to the passages 6, through the neck 2, to the annularchannel 16, which discharges over a ring or annular dam 17 concentricwith the axis of revolution, the ring being retained so thatsubstitutions of different rings can be effected for different con-*ditions by means of the collar 18 connected detachably with thebowlneck. f

As illustrated in the modified construction of Figs. 5 and 6, the bowl19, having the neck'20, is provided with the passages 21 and 22connected by the concentric chamber 23 for discharging the lightest sub-0 stance,:as oil, which flows thereto over the inner edge ofthe dam orring 24,- and the passages '25 for discharging together the two heaviersubstances, as wax and brine, which are delivered therefrom to thechannel 26 i p andthence over the dam or ring 27, themingledconstituents of different densities by the present invention, assume,that the S0 vessel 31 is provided with the dams 32 and 33 adjusted sothat the contact surface (1-11 of a resolved mixture (for instance ofbrine and wax free oil assumed for the purpose to separate by gravity)will, upon gravity separation, be between the upper and lower edges *ofthe dam 32 when the upper surface of oil is level with oroverflows thisdam and. the upper surface of the column of brine between the dams32'and 33 is level with or overflows the dam 33, as illustrated in Fig.7. If, now, oil containing precipitated wax is poured intothe oil in thevessel 31, the wax may be assumed to gravitate to the surface of thebrine and collect in a 5 layer between the oil and brine, having a topsurface 6-?) above the surface a-a and a bottom surface cc below thesurface a-a, asillustrated in Fig. 8. With, the desired adjustments andconditions (as the mingled constituents are continuously poured into thevessel), the wax would break the 'brineseal and leak under the dam 32'and escape over the dam 33 the lighter wax free oil flowing off over thedam '32. It 'will be understood that a change in the height of thedam 33varies the height of the adjacent column of brine and thus the plane ofcontact between the layers of oil and wax. A slight elevation of thisdam will elevate this contact surface so that the wax will occupy allthe separating space for the oil and the oil will flow over the dam 32without its wax having been separated, and a slight lowering of the 11dam 33 will lower this contact surface and permit the oilto escape withthe wax under dam 32 andover the dam 33, thus defeating the desiredpurpose of their separation. Likewise, if with dams properly adjusted,there should be a variation in the density of the brine,.the oil wouldescape with the wax in case of decreased brine density and the wax woulddischarge with the oil in case of increased brine density. It followsthen that, with this former type of separator or mode of operation, theefliciency of the separation of the two lighter substancesvaries withthe density of the heaviest substance and the adjustment of the dams.

'found that comparatively Considering now (diagrammatically andanalogously in illustration of the present invention as embodied inFigs. 1 and 5) the vessel 34, it is provided with the dams 35, 36 and 37having successively lower corresponding parts. The vessel 34 as shown inFig. 9, is designed for the discharge separately of oil, wax and brineresiectively, while this vessel, as shown in lig. 9, is designed for thedischarge of separated oil on the one hand and wax and brine together onthe other. The plane of contact (I -(Z of the layers of oil and wax isbetween the top and bottom of the dam 35, and the plane of contact c-eof the wax and brine between the bottoms of the dams 35 and 36; the dams35, 36 and 37 being adjusted to the positions for effecting the desiredoperations. The contact surface between the oil and wax is controlled bythe dams 35 and 36, and the contact surface between the wax and thebrine is controlled by the dams 36 and 37 The contact surface betweenthe Wax and the oil is independent of the height of the dam 37 and thedensity of the brine within certain limits to be specified, until thisdam becomes so high that the contact surface between the wax and brinelies between the top and bottom of the dam 35, with the result that thewax is sealed from its dam -36 and will discharge with the oil, or, onthe other hand, until the dam 37 becomes so low that the contact surfacebetween the wax and brine falls below the dam 36 when the wax escapesthrough, the brine column adjacent to the dam 37 For similar reasons thecontact surface between the oil and wax is also independent of thedensity of the brine within certain limits.

It follows from this that the efficiency of the separation of the twolighter substances is independent, within certain limits, of theadjustment of the brine dam and of the density of the brine.

Regard the construction shown in Figs. 10 and 10 (which is analogous tothat shown in Figs. 9 and 9) as a vertical section through a bowl 34divided on an axial plane and having dams 35, 36' and 37 for controllingthe flow through the respective discharge passa es, 35, 36" and 37", or35 and 36"--3 In practice, it has been wide variations can be made inthe distance of the weir or overflow edge of the dam 37 analogous to theparts 17 and 27 shownin Figs. 1 and 5, without changing the contactsurface between the oil and wax or at all interfering with theirseparation and separate discharge.

In the bowls of Figs. ,1 and 5, by reason of these characteristicfeatures, the separation of wax from oil is independent of variations inthe density of the brine and the oil mixture within certain limits, andalso of the adjustment of the brine dam within certain limits, for thecontact surface between them is within wide limits independent of thedensity of the brine and the adjustment of the brine dam, whereas in theformer practice it was directly dependent thereon and varied therewith.

The present invention is of distinct advantage in separating oil and waxwith a carrier liquid. for the position of the contact surface betweenthe oil and wax and therefore the separation varies with the relativespecific gravities of the oil and wax, which is approximatelyconstant inlots of oil obtained from the same source, whereas in the formerpractice the contact surfaces were dependent upon the specific gravitiesof the oil and brine which were liable to wide variations due to makingup the brine and oil solutions.

These advantages of the new method, while well illustrated by thespecific case of the separation of wax from oil, are equally true forseparation of any three substances.

Having described my invention, I claim:

1. The method of separating three substances having differcnt densitieswhich consists in subjecting them to centrifugal force and controllingthe distance of the contact surfaces of the centrifugally stratified Isists in centrifugally stratifying and controlling the place ofseparation of two of the contacting substances so that such place issubstantially independent of variations in the density of the thirdsubstance, and separately delivering the respective substances so thatthe density of the third substance can be varied without substantiallyvarying the distance from the center of rotation to the place ofseparation of the other substances.

3. The method of treating three substances of different densities whichconsists in centrifugally stratifying and controlling the place ofseparation of two of the substances so that such place is substantiallyindependent of, variations in the density 0 the third substance,separately delivering the respective substances so that the density ofthe third substance can be varied without substantially varying thedistance from the center of rotation of this place of separation of theother substances, and reuniting and discharging together two of thesepaated substances.

4. The method of separating wax from petroleum oil which consists inchilling the oil to precipitate the Wax, and subjecting the chilled oiltogether with an immiscible with three passages having independentcommunications therewith, a common outlet for two of said'passages andrespective controllmg means dlsposed at difierent distances from theaxis of the bowl, said bowl and controlling means adapted for stratifying three mixed substances and delivering said substances .through therespective passages. 1

In testimony whereof I have hereunto set my name this 31st day ofAugust,11920.

LEO D. JONES.

